Spiny Jewelbox

Spiny Jewelbox (Arcinella cornuta)

SHELL LENGTH: Approximately 1.5 inches (4 cm)

The Spiny Jewel Box is a bivalve found from the coasts of North Carolina to Florida and Texas. It is white; the interior may show tinges of pink or red. The shell itself is thick and heavy for its size. Fresh shell specimens will have more distinct erect tubular spines on the 7-9 rows (ribs) across the shell, radiating from the beak.

What are the spines for? It helps protect them from gastropod (other shell dwelling) predators like Moonsnails, who may want to drill into the shell and eat what is inside.

The Spiny Jewel box is a small mollusk with an unusual life pattern. Like most mollusks, it begins as a swimming larva and then attaches itself to a solid object, as would an oyster. But while oysters complete their life cycle firmly rooted, the jewel box works its way free and floats the later days of its life away. The jewel box's shell is approximately 1 1/2 -inches long, has an irregular shape, is white and bears many spines. The shells are commonly found on southern beaches, but most of the spines have been broken off by the surf. The mollusk itself has an excellent flavor and is used in chowders. The box is hard to detach and open, often requiring a hammer and chisel.

The Spiny Jewelbox is a filter feeder that feeds mainly on the plankton in the water.